Turn off "Use wireless networks" under Location services. Otherwise, Google's map service will constantly scan wireless networks to determine your location and eat up your battery.
1) Go to Settings > Location services and uncheck "Use wireless networks". Your battery drain might be Google services trying to continuously find your location.
2) Make sure Latitude is turned off by going into Maps > Settings > Location Settings and make sure Location Reporting is set to "Do not update my location" and Enable location sharing, Enable location history, and Automatic check-ins are all unchecked.